--- ray/src/px/pinterp.c	1990/01/04 10:12:49	1.11
+++ ray/src/px/pinterp.c	1990/01/05 11:34:27	1.15
@@ -17,11 +17,17 @@ static char SCCSid[] = "$SunId$ LBL";
 #define pscan(y)	(ourpict+(y)*ourview.hresolu)
 #define zscan(y)	(ourzbuf+(y)*ourview.hresolu)
 
-#define F_FORE	1			/* fill foreground */
-#define F_BACK	2			/* fill background */
+#define F_FORE		1		/* fill foreground */
+#define F_BACK		2		/* fill background */
 
+#define PACKSIZ		42		/* calculation packet size */
+
+#define RTCOM		"rtrace -h -ovl -fff -x %d %s"
+
 #define ABS(x)		((x)>0?(x):-(x))
 
+struct position {int x,y; float z;};
+
 VIEW	ourview = STDVIEW(512);		/* desired view */
 
 double	zeps = .02;			/* allowed z epsilon */
@@ -34,13 +40,21 @@ char	*progname;
 VIEW	theirview = STDVIEW(512);	/* input view */
 int	gotview;			/* got input view? */
 
-int	fill = F_FORE|F_BACK;		/* fill level */
+int	fill = F_FORE|F_BACK;		/* selected fill algorithm */
+extern int	backfill(), rcalfill();	/* fill functions */
+int	(*deffill)() = backfill;	/* selected fill function */
 COLR	backcolr = BLKCOLR;		/* background color */
+double	backz = 0.0;			/* background z value */
 
 double	theirs2ours[4][4];		/* transformation matrix */
 int	normdist = 1;			/* normalized distance? */
 
+int	childpid = -1;			/* id of fill process */
+FILE	*psend, *precv;			/* pipes to/from fill calculation */
+int	queue[PACKSIZ][2];		/* pending pixels */
+int	queuesiz;			/* number of pixels pending */
 
+
 main(argc, argv)			/* interpolate pictures */
 int	argc;
 char	*argv[];
@@ -84,10 +98,21 @@ char	*argv[];
 				break;
 			case 'c':				/* color */
 				check(3,3);
+				deffill = backfill;
 				setcolr(backcolr, atof(argv[i+1]),
 					atof(argv[i+2]), atof(argv[i+3]));
 				i += 3;
 				break;
+			case 'z':				/* z value */
+				check(3,1);
+				deffill = backfill;
+				backz = atof(argv[++i]);
+				break;
+			case 'r':				/* rtrace */
+				check(3,1);
+				deffill = rcalfill;
+				calstart(RTCOM, argv[++i]);
+				break;
 			default:
 				goto badopt;
 			}
@@ -159,7 +184,7 @@ char	*argv[];
 			goto userr;
 		}
 						/* check arguments */
-	if (argc-i < 2 || (argc-i)%2)
+	if ((argc-i)%2)
 		goto userr;
 						/* set view */
 	if (err = setview(&ourview)) {
@@ -167,20 +192,20 @@ char	*argv[];
 		exit(1);
 	}
 						/* allocate frame */
-	ourpict = (COLR *)calloc(ourview.hresolu*ourview.vresolu,sizeof(COLR));
+	ourpict = (COLR *)malloc(ourview.hresolu*ourview.vresolu*sizeof(COLR));
 	ourzbuf = (float *)calloc(ourview.hresolu*ourview.vresolu,sizeof(float));
-	if (ourpict == NULL || ourzbuf == NULL) {
-		perror(progname);
-		exit(1);
-	}
+	if (ourpict == NULL || ourzbuf == NULL)
+		syserror();
 							/* get input */
 	for ( ; i < argc; i += 2)
 		addpicture(argv[i], argv[i+1]);
 							/* fill in spaces */
 	if (fill&F_BACK)
-		fillpicture();
-	else
 		backpicture();
+	else
+		fillpicture();
+							/* close calculation */
+	caldone();
 							/* add to header */
 	printargs(argc, argv, stdout);
 	if (gotvfile) {
@@ -229,8 +254,8 @@ char	*pfile, *zspec;
 	FILE	*pfp, *zfp;
 	char	*err;
 	COLR	*scanin;
-	float	*zin, *zlast;
-	int	*plast;
+	float	*zin;
+	struct position	*plast;
 	int	y;
 					/* open picture file */
 	if ((pfp = fopen(pfile, "r")) == NULL) {
@@ -255,12 +280,10 @@ char	*pfile, *zspec;
 					/* allocate scanlines */
 	scanin = (COLR *)malloc(theirview.hresolu*sizeof(COLR));
 	zin = (float *)malloc(theirview.hresolu*sizeof(float));
-	plast = (int *)calloc(theirview.hresolu, sizeof(int));
-	zlast = (float *)calloc(theirview.hresolu, sizeof(float));
-	if (scanin == NULL || zin == NULL || plast == NULL || zlast == NULL) {
-		perror(progname);
-		exit(1);
-	}
+	plast = (struct position *)calloc(theirview.hresolu,
+						sizeof(struct position));
+	if (scanin == NULL || zin == NULL || plast == NULL)
+		syserror();
 					/* get z specification or file */
 	if ((zfp = fopen(zspec, "r")) == NULL) {
 		double	zvalue;
@@ -284,13 +307,12 @@ char	*pfile, *zspec;
 			fprintf(stderr, "%s: read error\n", zspec);
 			exit(1);
 		}
-		addscanline(y, scanin, zin, plast, zlast);
+		addscanline(y, scanin, zin, plast);
 	}
 					/* clean up */
 	free((char *)scanin);
 	free((char *)zin);
 	free((char *)plast);
-	free((char *)zlast);
 	fclose(pfp);
 	if (zfp != NULL)
 		fclose(zfp);
@@ -333,19 +355,15 @@ register VIEW	*vw1, *vw2;
 }
 
 
-addscanline(y, pline, zline, lasty, lastyz)	/* add scanline to output */
+addscanline(y, pline, zline, lasty)	/* add scanline to output */
 int	y;
 COLR	*pline;
 float	*zline;
-int	*lasty;			/* input/output */
-float	*lastyz;		/* input/output */
+struct position	*lasty;		/* input/output */
 {
 	extern double	sqrt();
 	double	pos[3];
-	int	lastx = 0;
-	double	lastxz = 0;
-	double  zt;
-	int	xpos, ypos;
+	struct position	lastx, newpos;
 	register int	x;
 
 	for (x = theirview.hresolu-1; x >= 0; x--) {
@@ -361,62 +379,86 @@ float	*lastyz;		/* input/output */
 			pos[1] *= pos[2];
 		}
 		multp3(pos, pos, theirs2ours);
-		if (pos[2] <= 0)
+		if (pos[2] <= 0) {
+			lasty[x].z = lastx.z = 0;	/* mark invalid */
 			continue;
+		}
 		if (ourview.type == VT_PER) {
 			pos[0] /= pos[2];
 			pos[1] /= pos[2];
 		}
 		pos[0] += .5*ourview.hresolu;
 		pos[1] += .5*ourview.vresolu;
-		if (pos[0] < 0 || (xpos = pos[0]) >= ourview.hresolu
-			|| pos[1] < 0 || (ypos = pos[1]) >= ourview.vresolu)
-			continue;
+		newpos.x = pos[0];
+		newpos.y = pos[1];
+		newpos.z = zline[x];
 					/* add pixel to our image */
-		zt = 2.*zeps*zline[x];
-		addpixel(xpos, ypos,
-			(fill&F_FORE && ABS(zline[x]-lastxz) <= zt)
-				? lastx - xpos : 1,
-			(fill&F_FORE && ABS(zline[x]-lastyz[x]) <= zt)
-				? lasty[x] - ypos : 1,
-			pline[x], pos[2]);
-		lastx = xpos;
-		lasty[x] = ypos;
-		lastxz = lastyz[x] = zline[x];
+		if (pos[0] >= 0 && newpos.x < ourview.hresolu
+				&& pos[1] >= 0 && newpos.y < ourview.vresolu) {
+			addpixel(&newpos, &lastx, &lasty[x], pline[x], pos[2]);
+			lasty[x].x = lastx.x = newpos.x;
+			lasty[x].y = lastx.y = newpos.y;
+			lasty[x].z = lastx.z = newpos.z;
+		} else
+			lasty[x].z = lastx.z = 0;	/* mark invalid */
 	}
 }
 
 
-addpixel(xstart, ystart, width, height, pix, z)	/* fill in area for pixel */
-int	xstart, ystart;
-int	width, height;
+addpixel(p0, p1, p2, pix, z)		/* fill in pixel parallelogram */
+struct position	*p0, *p1, *p2;
 COLR	pix;
 double	z;
 {
-	register int	x, y;
-					/* make width and height positive */
-	if (width < 0) {
-		width = -width;
-		xstart = xstart-width+1;
-	} else if (width == 0)
-		width = 1;
-	if (height < 0) {
-		height = -height;
-		ystart = ystart-height+1;
-	} else if (height == 0)
-		height = 1;
-					/* fill pixel(s) within rectangle */
-	for (y = ystart; y < ystart+height; y++)
-		for (x = xstart; x < xstart+width; x++)
-			if (zscan(y)[x] <= 0
-					|| zscan(y)[x]-z > zeps*zscan(y)[x]) {
+	double	zt = 2.*zeps*p0->z;		/* threshold */
+	int	s1x, s1y, s2x, s2y;		/* step sizes */
+	int	l1, l2, c1, c2;			/* side lengths and counters */
+	int	p1isy;				/* p0p1 along y? */
+	int	x1, y1;				/* p1 position */
+	register int	x, y;			/* final position */
+
+					/* compute vector p0p1 */
+	if (fill&F_FORE && ABS(p1->z-p0->z) <= zt) {
+		s1x = p1->x - p0->x;
+		s1y = p1->y - p0->y;
+		l1 = ABS(s1x);
+		if (p1isy = (ABS(s1y) > l1))
+			l1 = ABS(s1y);
+	} else {
+		l1 = s1x = s1y = 1;
+		p1isy = -1;
+	}
+					/* compute vector p0p2 */
+	if (fill&F_FORE && ABS(p2->z-p0->z) <= zt) {
+		s2x = p2->x - p0->x;
+		s2y = p2->y - p0->y;
+		if (p1isy == 1)
+			l2 = ABS(s2x);
+		else {
+			l2 = ABS(s2y);
+			if (p1isy != 0 && ABS(s2x) > l2)
+				l2 = ABS(s2x);
+		}
+	} else
+		l2 = s2x = s2y = 1;
+					/* fill the parallelogram */
+	for (c1 = l1; c1-- > 0; ) {
+		x1 = p0->x + c1*s1x/l1;
+		y1 = p0->y + c1*s1y/l1;
+		for (c2 = l2; c2-- > 0; ) {
+			x = x1 + c2*s2x/l2;
+			y = y1 + c2*s2y/l2;
+			if (zscan(y)[x] <= 0 || zscan(y)[x]-z
+						> zeps*zscan(y)[x]) {
 				zscan(y)[x] = z;
 				copycolr(pscan(y)[x], pix);
 			}
+		}
+	}
 }
 
 
-fillpicture()				/* fill in empty spaces */
+backpicture()				/* background fill algorithm */
 {
 	int	*yback, xback;
 	int	y;
@@ -424,10 +466,8 @@ fillpicture()				/* fill in empty spaces */
 	register int	x, i;
 							/* get back buffer */
 	yback = (int *)malloc(ourview.hresolu*sizeof(int));
-	if (yback == NULL) {
-		perror(progname);
-		return;
-	}
+	if (yback == NULL)
+		syserror();
 	for (x = 0; x < ourview.hresolu; x++)
 		yback[x] = -2;
 	/*
@@ -473,7 +513,7 @@ fillpicture()				/* fill in empty spaces */
 				 * this pixel.  If not, use background color.
 				 */
 				if (xback < 0 && yback[x] < 0) {
-					copycolr(pscan(y)[x], backcolr);
+					(*deffill)(x,y);
 					continue;
 				}
 				/*
@@ -484,10 +524,13 @@ fillpicture()				/* fill in empty spaces */
 					|| (xback >= 0 && ABS(x-xback) <= 1)
 					|| ( ABS(y-yback[x]) > 1
 						&& zscan(yback[x])[x]
-						< zscan(y)[xback] ) )
+						< zscan(y)[xback] ) ) {
 					copycolr(pscan(y)[x],pscan(y)[xback]);
-				else
+					zscan(y)[x] = zscan(y)[xback];
+				} else {
 					copycolr(pscan(y)[x],pscan(yback[x])[x]);
+					zscan(y)[x] = zscan(yback[x])[x];
+				}
 			} else {				/* full pixel */
 				yback[x] = -2;
 				xback = -2;
@@ -497,14 +540,14 @@ fillpicture()				/* fill in empty spaces */
 }
 
 
-backpicture()				/* paint in empty pixels */
+fillpicture()				/* paint in empty pixels with default */
 {
 	register int	x, y;
 
 	for (y = 0; y < ourview.vresolu; y++)
 		for (x = 0; x < ourview.hresolu; x++)
 			if (zscan(y)[x] <= 0)
-				copycolr(pscan(y)[x], backcolr);
+				(*deffill)(x,y);
 }
 
 
@@ -514,10 +557,8 @@ writepicture()				/* write out picture */
 
 	fputresolu(YMAJOR|YDECR, ourview.hresolu, ourview.vresolu, stdout);
 	for (y = ourview.vresolu-1; y >= 0; y--)
-		if (fwritecolrs(pscan(y), ourview.hresolu, stdout) < 0) {
-			perror(progname);
-			exit(1);
-		}
+		if (fwritecolrs(pscan(y), ourview.hresolu, stdout) < 0)
+			syserror();
 }
 
 
@@ -535,10 +576,8 @@ char	*fname;
 		exit(1);
 	}
 	if (donorm
-	&& (zout = (float *)malloc(ourview.hresolu*sizeof(float))) == NULL) {
-		perror(progname);
-		exit(1);
-	}
+	&& (zout = (float *)malloc(ourview.hresolu*sizeof(float))) == NULL)
+		syserror();
 	for (y = ourview.vresolu-1; y >= 0; y--) {
 		if (donorm) {
 			double	vx, yzn2;
@@ -572,4 +611,120 @@ register char	*s;
 				&& *s != 'e' && *s != 'E' && *s != '+')
 			return(0);
 	return(1);
+}
+
+
+backfill(x, y)				/* fill pixel with background */
+int	x, y;
+{
+	register BYTE	*dest = pscan(y)[x];
+
+	copycolr(dest, backcolr);
+	zscan(y)[x] = backz;
+}
+
+
+calstart(prog, args)			/* start fill calculation */
+char	*prog, *args;
+{
+	char	combuf[512];
+	int	p0[2], p1[2];
+
+	if (childpid != -1) {
+		fprintf(stderr, "%s: too many calculations\n", progname);
+		exit(1);
+	}
+	sprintf(combuf, prog, PACKSIZ, args);
+	if (pipe(p0) < 0 || pipe(p1) < 0)
+		syserror();
+	if ((childpid = vfork()) == 0) {	/* fork calculation */
+		close(p0[1]);
+		close(p1[0]);
+		if (p0[0] != 0) {
+			dup2(p0[0], 0);
+			close(p0[0]);
+		}
+		if (p1[1] != 1) {
+			dup2(p1[1], 1);
+			close(p1[1]);
+		}
+		execl("/bin/sh", "sh", "-c", combuf, 0);
+		perror("/bin/sh");
+		_exit(127);
+	}
+	if (childpid == -1)
+		syserror();
+	close(p0[0]);
+	close(p1[1]);
+	if ((psend = fdopen(p0[1], "w")) == NULL)
+		syserror();
+	if ((precv = fdopen(p1[0], "r")) == NULL)
+		syserror();
+	queuesiz = 0;
+}
+
+
+caldone()				/* done with calculation */
+{
+	int	pid;
+
+	if (childpid == -1)
+		return;
+	if (fclose(psend) == EOF)
+		syserror();
+	clearqueue();
+	fclose(precv);
+	while ((pid = wait(0)) != -1 && pid != childpid)
+		;
+	childpid = -1;
+}
+
+
+rcalfill(x, y)				/* fill with ray-calculated pixel */
+int	x, y;
+{
+	FVECT	orig, dir;
+	float	outbuf[6];
+
+	if (queuesiz >= PACKSIZ) {	/* flush queue */
+		if (fflush(psend) == EOF)
+			syserror();
+		clearqueue();
+	}
+					/* send new ray */
+	rayview(orig, dir, &ourview, x+.5, y+.5);
+	outbuf[0] = orig[0]; outbuf[1] = orig[1]; outbuf[2] = orig[2];
+	outbuf[3] = dir[0]; outbuf[4] = dir[1]; outbuf[5] = dir[2];
+	if (fwrite(outbuf, sizeof(float), 6, psend) < 6)
+		syserror();
+					/* remember it */
+	queue[queuesiz][0] = x;
+	queue[queuesiz][1] = y;
+	queuesiz++;
+}
+
+
+clearqueue()				/* get results from queue */
+{
+	float	inbuf[4];
+	register int	i;
+
+	for (i = 0; i < queuesiz; i++) {
+		if (fread(inbuf, sizeof(float), 4, precv) < 4) {
+			fprintf(stderr, "%s: read error in clearqueue\n",
+					progname);
+			exit(1);
+		}
+		setcolr(pscan(queue[i][1])[queue[i][0]],
+				inbuf[0], inbuf[1], inbuf[2]);
+		zscan(queue[i][1])[queue[i][0]] = inbuf[3];
+	}
+	queuesiz = 0;
+}
+
+
+syserror()			/* report error and exit */
+{
+	perror(progname);
+	exit(1);
 }